Reliable video broadcasts via protected Steiner trees

The introduction of the latest generation of ROADMs in the communication long-haul transport networks allows network planners to consider some new cost-effective design alternatives. Specifically, for video broadcast services ROADM wavelength drop-and-continue technology enables simple wavelength connections at each node via a tree-like topology, and the intelligent control plane permits the use of various shared protection schemes (with failure restoration switching times comparable to SONET BLSR). In this article we formulate models for reliable TV/video broadcast. We consider the network topologies based on minimum spanning trees. The objective is to minimize the total network cost while ensuring that the broadcast, originating in one (or two) source node(s), is delivered to a set of destination nodes and the network will tolerate at least one single link failure. The resulting protected tree networks are illustrated, and the cost of protection strategies is analyzed.